Bonette last week testified that Kotze had sawn off both of her nipples during a prolonged torture session, after which the other three accused had taken turns to rape her.

She could hear her son begging Kotze for his life before she heard three shots.

DNA expert Lt Col Carin Botha testified that no semen or DNA could be found on any samples taken from Bonette.

Botha testified that there were several possibilities why semen could not be found on the victim or any of the other exhibits, including the victim urinating, the alleged rapist using a condom or no sex taking place.

The period between the incident and the samples being collected could also have played a role in why no semen could be found.

Kotze's three alleged accomplices all claimed they had simulated sex with Bonette because they were afraid Kotze was going to kill them, but had not raped her because they could not get erections.